Control of conception has been an important medical endeavor for many years and instructions for the manufacture of contraceptive devices and compositions are found in some of the earliest known medical manuscripts. Presently, contraceptive technologies rely upon pharmaceutical a nd mechanical methods. Pharmaceutical methods involve the use of medicinal compounds which prevent pregnancy by interfering with ovulation, implantation or spermatogenesis. Mechanical methods are directed to preventing contact of ovum and sperm and involve the use of mechanical barriers and spermicidal compounds.
Because of the increasing concern with the side effects of pharmaceutical compositions, mechanical methods of contraception are increasing in popularity. Additionally, concern with sexually transmitted diseases has engendered a renewed interest in barrier type devices.
The cervical cap is one of the earliest types of mechanical contraceptives available, having been introduced over 150 years ago. The cervical cap is a generally rigid, relatively small device fitted directly onto the cervix where it forms a barrier to the passage of spermatozoa thereinto. Although the cervical cap has been available for a relatively long period of time it is of rather limited use. In order to obtain a good fit, it is generally required that wax or latex impressions of the cervix be taken and these impressions utilized to fabricate a custom fitted cap. Such fitting is expensive, time consuming and requires the assistance of highly trained personnel. Insertion and removal of the cervical cap is relatively difficult and frequently must be done by trained personnel. The cap is generally left in place for relatively long periods of time and this placement can encourage undesired side effects such as the growth of anaerobic bacteria in the uterus, toxic shock syndrome and mechanical damage such as cervical erosion. Such technology is described in U.S. Pat. Nos. 4,517,970; 4,401,534 and 4,467,789.
A more commonly utilized type of barrier contraceptive is the diaphragm, which has been available since the end of the 19th Century and which has been in relatively wide use in the last thirty years. The diaphragm presently utilized is generally similar in design to that first invented in 1882 by Dr. C. Hasse. It is comprised of a flexible rubber barrier of generally circular shape having a rigid, thickened rim reinforced with a metal spring. In use, the diaphragm is inserted in the vagina so that it forms a barrier seal protecting the opening of the cervix.
While presently utilized diaphragms are quite well accepted, use of such devices is not without problems. The proper fitting of diaphragms is essential if reliable contraception is to be obtained. The diaphragm must contact the vaginal wall uniformly and tightly so as to prevent spermatozoa from passing therearound. Accordingly, presently available contraceptive diaphragms are provided in a wide range of sizes and must be fitted carefully by trained medical personnel. Additionally, the user must be trained in proper methods of insertion if the function of the diaphragm is to be reliable. An improperly fitted, or improperly inserted diaphragm may become dislodged during sexual activity thereby permitting conception to occur.
Since proper fit is so crucial to diaphragm function, women utilizing such devices should be carefully monitored. If a weight gain or loss of more than 15 pounds occurs it is generally advised that the diaphragm be refitted. Similarly, child birth, abdominal surgery or other such events will necessitate refitting of a contraceptive diaphragm. The rigid rim of such diaphragms can cause problems with its use. Many women cannot tolerate such a device because of the size or shape of their vaginal walls or cervix. In addition, the rigid rim can in some instances cause pressure ulceration to occur. Accordingly, it will be appreciated that there is a need for a device which eliminates these shortcomings of the presently available diaphragm.
Contraceptive sponges are another class of devices enjoying increasing popularity. The contraceptive sponge is a generally flattened, cylindrical device made of resilient polyurethane foam or similar materials impregnated with a spermicidal compound. Such a device is not strictly speaking a barrier insofar as it does not impose any impenetrable cover over the cervix. Instead, it is believed that the contraceptive sponge functions by spermicidal action. The contraceptive sponge need not be custom fitted for individual users and accordingly may be purchased over the counter without prescription, and for this reason is enjoying widespread use. The contraceptive sponge is not without shortcomings however. In general the contraceptive sponge has a lower reliability rate than does a properly fitted diaphragm. Problems occur because of dislodgement of the device, bypass of the device or ineffectiveness of the spermicide. Dislodgement and bypass can occur during sexual activity when the penis moves past the sponge pushing it away from the cervix. Ejaculation can then occur in the vicinity of the cervix and spermatozoa can pass thereinto without being exposed to the spermicidal compound in the sponge.
In addition to problems of reliability, there are also problems of a mechanical nature involved in the use of contraceptive sponges. In many instances, users have found it difficult to remove such sponges from the vaginal cavity. In those cases, the sponge tears or breaks thereby preventing removal, and medical assistance must be resorted to remove all traces of the sponge. In other instances, the use of contraceptive sponges has been associated with toxic shock syndrome. Some women also have problems retaining the sponge for a sufficient length of time to insure contraception.
Accordingly, it will be appreciated that there is a need for a contraceptive device which enjoys the reliability and general safety of heretofore employed contraceptive diaphragms and which has the additional advantages of presently utilized contraceptive sponges insofar as it eliminates the need for fitting by trained personnel. Such a contraceptive device could readily be sold over the counter in one or two basic sizes to accommodate most women. It may be preferable in some instances to fabricate such devices as one time disposable items whereas in other instances a reusable contraceptive of this type will be desired. It is further desired that such contraceptive devices be relatively easy to insert and remove and that they have sufficient flexibility so as to prevent the formation of ulcers or erosions.
The present invention provides for a barrier type contraceptive fulfilling these needs. The contraceptive of the present invention is a generally umbrella shaped article which may be readily folded into an elongated or fusiform shape for insertion or removal. Once in place, the contraceptive device of the present invention is adapted to expand so as to uniformly contact the vaginal walls thereby forming a tight barrier seal. The contraceptive of the present invention may be utilized in conjunction with spermicidal compounds and may further include reservoirs for such compounds as well as a handle or loop for removal. In addition to being utilized as a contraceptive device, the umbrella-like diaphragm of the present invention may be utilized as a therapeutic device adapted to release medicinal compounds into the vaginal environment. These and other advantages and features of the present invention will be readily apparent from the summary, drawings, detailed description and claims which follow.